Fehler in Lightroom bei Panorama zusammenfügen

The first thing that you should try is to switch off the GPU support from the Lightroom preferences and check if that helps to fix the issue.

Go to Lightroom > Preferences > Performance tab > Uncheck "Use Graphics Processor" > Restart Lightroom.

https://helpx.adobe.com/lightroom-classic/kb/troubleshoot-gpu.html

Another step is to try to reset the Lightroom preferences.

https://www.lightroomqueen.com/how-do-i-reset-lightrooms-preferences/

It's recommended to backup your preferences before you reset the preferences to the default settings:

https://helpx.adobe.com/lightroom-classic/kb/preference-file-and-other-file-locations.html

Do you have build in a external graphic card like a NVidia Geforce or a similar card? 

If yes, the try to disable the CPU internal graphic device. 

See  section "Solution 4: GPU and graphics driver troubleshooting steps", step 6 in this document: Troubleshoot GPU issues | Lightroom Classic (adobe.com)

Please provide also a copy of your 'System Info'. This can be get from the LrC Help > System Info menu item. There's a copy button in the System Info dialog. Press this button and paste the info into your next forum post.